Multiscale Observation of Magnetotail Reconnection Onset: 1. Macroscopic Dynamics

Details

• Journal Title:
  Journal of Geophysical Research: Space Physics
• Personal Author:
  Genestreti, K.J. ; Farrugia, C.J. ; Lu, S. ; Vines, S.K. ; Reiff, P.H. ; Phan, T. ; Baker, D.N. ; Leonard, T.W.
• NOAA Program & Office:
  NESDIS (National Environmental Satellite, Data, and Information Service) ; NCEI (National Centers for Environmental Information) ; CIRES (Cooperative Institute for Research in Environmental Sciences)
• Description:
  We analyze a magnetotail reconnection onset event on 3 July 2017 that was observed under otherwise quiescent magnetospheric conditions by a fortuitous conjunction of six space and ground-based observatories. The study investigates the large-scale coupling of the solar wind–magnetosphere system that precipitated the onset of the magnetotail reconnection, focusing on the processes that thinned and stretched the cross-tail current layer in the absence of significant flux loading during a 2-hr-long preconditioning phase. It is demonstrated with data in the (a) upstream solar wind, (b) at the low-latitude magnetopause, (c) in the high-latitude polar cap, and (d) in the magnetotail that the typical picture of solar wind-driven current sheet thinning via flux loading does not appear relevant for this particular event. We find that the current sheet thinning was, instead, initiated by a transient solar wind pressure pulse and that the current sheet thinning continued even as the magnetotail and solar wind pressures decreased. We suggest that field line curvature-induced scattering (observed by magnetospheric multiscale) and precipitation (observed by Defense Meteorological Satellite Program) of high-energy thermal protons may have evacuated plasma sheet thermal energy, which may require a thinning of the plasma sheet to preserve pressure equilibrium with the solar wind.
• Keywords:
  Magnetosphere Magnetotails Solar Wind Solar Wind
• Source:
  Journal of Geophysical Research: Space Physics, 128, e2023JA031758
• DOI:
  https://doi.org/10.1029/2023JA031758
• Format:
  PDF
• Document Type:
  Journal Article
• Rights Information:
  Other
• Compliance:
  Submitted
• Main Document Checksum:
  urn:sha-512:1ca3d954c09334d8d05f7a3c165f42ba72dd16e939f5f1a7b1b5778e2a51db17bd4204140e0534e76df3bb2366ba70729e84150c47681536355ea2c6a1123b83
• Download URL:
  https://repository.library.noaa.gov/view/noaa/66357/noaa_66357_DS1.pdf
• File Type:
  [PDF - 4.45 MB ]